refactor: remove dead AppState.History and ServiceEarning.Delta (#48)

Both were populated/computed on every GetAppState but never read by the frontend
(they existed only in the type contract, never accessed). AppState.History ran a
200-row ListEarningsHistory query on every state read — now removed, which also
drops the query from the frequent event-driven refresh added recently. Removed
the now-orphaned store.ListEarningsHistory (its only caller) and trimmed its test
to keep the ListLatestEarnings coverage. Removed the dead fields from the frontend
bindings (wails.d.ts, models.ts) to keep the type contract in sync.

Verified: go build/vet/test -race and the frontend tsc && vite build all pass.

Author: GeiserX

app.go

@@ -149,7 +149,6 @@ type AppState struct {
 	Services      []catalog.Service      `json:"services"`
 	Deployments   []store.Deployment     `json:"deployments"`
 	Earnings      []store.EarningsRecord `json:"earnings"`
-	History       []store.EarningsRecord `json:"history"`
 	Guides        []runtime.InstallGuide `json:"guides"`
 	Notifications []Notification         `json:"notifications"`
 	Currencies    []string               `json:"currencies"`
@@ -189,7 +188,6 @@ type ServiceEarning struct {
 	Currency       string          `json:"currency"`
 	BalanceDisplay float64         `json:"balanceDisplay"`
 	Convertible    bool            `json:"convertible"`
-	Delta          float64         `json:"delta"`
 	Error          string          `json:"error"`
 	Cashout        CashoutProgress `json:"cashout"`
 }
@@ -272,7 +270,6 @@ func (a *App) GetAppState() (AppState, error) {
 		Services:      a.catalog.ListVisible(),
 		Deployments:   a.store.ListDeployments(),
 		Earnings:      a.store.ListLatestEarnings(),
-		History:       a.store.ListEarningsHistory(200),
 		Guides:        runtime.InstallGuides(),
 		Notifications: a.notifications(runtimeStatus),
 		Currencies:    supportedCurrencies(),
@@ -489,10 +486,6 @@ func (a *App) computeEarningsSummary() EarningsSummary {
 				se.BalanceDisplay = conv
 			}
 		}
-		// Native day-over-day change from the last two collected days.
-		if days := daysByPlat[rec.Platform]; len(days) >= 2 {
-			se.Delta = perPlat[rec.Platform][days[len(days)-1]] - perPlat[rec.Platform][days[len(days)-2]]
-		}
 		cp := CashoutProgress{
 			MinAmount:    cash.MinAmount,
 			Currency:     cash.Currency,

frontend/src/wails.d.ts

@@ -27,7 +27,6 @@ export interface AppState {
   services: Service[];
   deployments: Deployment[] | null;
   earnings: EarningsRecord[] | null;
-  history: EarningsRecord[] | null;
   guides: InstallGuide[];
   notifications: NotificationItem[];
   currencies: string[];
@@ -55,7 +54,6 @@ export interface ServiceEarning {
   currency: string;
   balanceDisplay: number;
   convertible: boolean;
-  delta: number;
   error: string;
   cashout: CashoutProgress;
 }

frontend/wailsjs/go/models.ts

@@ -309,7 +309,6 @@ export namespace main {
 	    services: catalog.Service[];
 	    deployments: store.Deployment[];
 	    earnings: store.EarningsRecord[];
-	    history: store.EarningsRecord[];
 	    guides: runtime.InstallGuide[];
 	    notifications: Notification[];
 	    currencies: string[];
@@ -325,7 +324,6 @@ export namespace main {
 	        this.services = this.convertValues(source["services"], catalog.Service);
 	        this.deployments = this.convertValues(source["deployments"], store.Deployment);
 	        this.earnings = this.convertValues(source["earnings"], store.EarningsRecord);
-	        this.history = this.convertValues(source["history"], store.EarningsRecord);
 	        this.guides = this.convertValues(source["guides"], runtime.InstallGuide);
 	        this.notifications = this.convertValues(source["notifications"], Notification);
 	        this.currencies = source["currencies"];

internal/store/store.go

@@ -262,33 +262,6 @@ func (s *Store) ListLatestEarnings() []EarningsRecord {
 	return out
 }
 
-func (s *Store) ListEarningsHistory(limit int) []EarningsRecord {
-	if limit <= 0 {
-		limit = 200
-	}
-	rows, err := s.db.Query(`
-		SELECT platform, balance, currency, error, created_at
-		FROM earnings
-		ORDER BY created_at DESC
-		LIMIT ?
-	`, limit)
-	if err != nil {
-		return nil
-	}
-	defer rows.Close()
-	var out []EarningsRecord
-	for rows.Next() {
-		var record EarningsRecord
-		if err := rows.Scan(&record.Platform, &record.Balance, &record.Currency, &record.Error, &record.CreatedAt); err == nil {
-			out = append(out, record)
-		}
-	}
-	for i, j := 0, len(out)-1; i < j; i, j = i+1, j-1 {
-		out[i], out[j] = out[j], out[i]
-	}
-	return out
-}
-
 // ListDailyBalances returns the latest successful balance (rows whose error column
 // is empty) for each (platform, day) over the last daysBack days. The latest row
 // per (platform, day) is chosen by MAX(id), not MAX(created_at): created_at is

internal/store/store_test.go

@@ -367,7 +367,7 @@ func TestDeploymentRoundTrip(t *testing.T) {
 	}
 }
 
-func TestEarningsLatestAndHistory(t *testing.T) {
+func TestEarningsLatest(t *testing.T) {
 	s := openTestStore(t)
 
 	if _, err := s.SaveEarnings(EarningsRecord{Platform: "storj", Balance: 1.0, Currency: "USD", CreatedAt: "2026-01-01T00:00:00Z"}); err != nil {
@@ -384,15 +384,6 @@ func TestEarningsLatestAndHistory(t *testing.T) {
 	if latest[0].Balance != 2.5 {
 		t.Fatalf("expected the latest balance 2.5, got %v", latest[0].Balance)
 	}
-
-	history := s.ListEarningsHistory(10)
-	if len(history) != 2 {
-		t.Fatalf("expected 2 history records, got %d", len(history))
-	}
-	// History is reversed to oldest-first.
-	if history[0].Balance != 1.0 || history[1].Balance != 2.5 {
-		t.Fatalf("unexpected history order: %+v", history)
-	}
 }
 
 // TestListLatestEarningsTieBreakByID pins the deterministic intra-second